Sighting and range finding device for firearms



33-261. OR 2.5mm: W"UHHUUWI "Aug. 7, 1951 s o 2,563,193

I SIGHTING AND RANGE FINDING DEVICE FOR FIREARMS Filed March 11, 1946 2 Sheets-Sheet l L/CW I11 veular Zarr 213523 2202? My MZeys MAHW ROOM.

7, 1951 L. M. SEYMORE 2,563,193

SIGHTING AND RANGE FINDING DEVICE FOR FIREARMS Filed March 11, 1946 2 Sheets-Sheet 2 Inventor W 15027 21," Sqynzore Patented Aug. 7, 1951 EARGH scum OFFICE SIGHTING AND RANGE FINDING DEVICE FOR FIREARMS Larry M. Seymore, West Los Angeles, Calif.

Application March 11, 1946, Serial No. 653,592

1 Claim. 1

This invention relates to sighting and range finding devices for firearms and it has for its main object to provide a device of the type mentioned which will permit the rapid locating of a moving target within the sighting device and a precise evaluation of the distance of the target.

It is a further object of the invention to provide a sighting device of the type mentioned which is removably attached to the rifle or gun and which may therefore be changed to suit the target for which the gun or rifle is to be mainly used.

It is a further object of the invention to provide a front sighting device consisting of at least two circular concentric bands, which permit the precise evaluation of the distance of a target of known size, by making a diameter of one of the sighting bands equal to the apparent size of the target in the plane of the sighting device, when said target is at a predetermined distance.

It is a further object of the invention to provide a front sighting device for firearms consisting of two substantially circular sighting bands disposed one inside the other and arranged concentrically with respect to each other and with respect to the axis or sight line circular sighting bands arranged within or close to a plane passing through the center of the head of the firearm, the diameter of the inner circular sighting band being equal to the apparent size of a known target in the plane of the sighting device when the said target is located at the maximum range of efiicient action of the firearm.

It is a still further object of the invention to provide a front sighting and range finding device of the type described for a shot gun, consisting of two concentric circular sighting bands arranged so as to have their thin edges in the sighting line and located in the vicinity of the bead of the firearm, which are of such size that the diameter of the inner circular sighting band equals the apparent size of a target of known dimensions when in the plane of maximum efiicient range, while the diameter of the outer sighting band equals the apparent diameter of the straying zone of the shot gun within said plane.

Further objects will be apparent from the following detailed specification in which several modifications and embodiments of the invention are illustrated and described.

It is, however, to be understood that the modifications shown are illustrative and are to be considered as examples illustrating by means of specific constructions the practical application of the invention in certain cases. These examples therefore do not delimit the scope of the inven- 2 tion but serve to explain the general constructive principles to be applied to the expert skilled in this art so as to enable him to find further modifications and embodiments of the invention. These further embodiments which are foreshadowed in the present specification, as far as included in the annexed claim, are part of the invention and do not form a departure therefrom.

In the accompanying drawing:

Figure 1 is an elevational front view of the sighting and range finding device according to the invention.

Figure 2 is an elevational sectional view of one modification of the device, the section being a longitudinal section along a plane passing through the axis of the barrel and indicated at 22 in Figure 1.

Figure 3 is a sectional plan view of the device, the section being taken along a horizontal plane indicated at 3-3 in Figure 2.

Figure 4 is a pictorial view illustrating the use of the invention.

Figure 5 is a diagram illustrating the sighting and range finding operation.

Figure 6 is an elevational front view of a modification of the invention.

Figures '7 and 8 are an elevational front view and an elevational sectional view at right angle thereto, respectively, of a modification to be used in connection with double barrelled guns or rifles.

The sighting and range finding device according to my invention consists in a front sight gen-' erally indicated by the reference numeral l0 and adapted to be mounted on the front end of a rifle or gun barrel. It comprises two bands or strips II and I2, of circular and approximately semi-circular shape, respectively, which are con-;'

centrically arranged around an axis or sight line which passes through the head 13 of the rifle or one end and carrying a milled nut [9 at the other end.

The bands I l and l2 forming the sight may be. secured to the clamping band It by spot Welding or torch welding or in any other appropriate manner, for instance, by rivets.

This removable sight has many advantages as it may be carried in the pocket or in a bag when the rifle or gun is not in use and as it is possible 3 to use difierent sights on the gun adapted for difierent purposes.

The spot on which the sighting device is to be mounted has, however, to be a fixed one. As seen in Figures 2 and 3 the bead l3 may serve to determine the exact spot where it is to be mounted. It is, of course, also possible to provide a shallow recess or short longitudinal slot in the clamping band [4 into which the bead may enter, if the clamping band is made of a material which will permit the weakening of the cross section at the end without deformation.

The outer band I l is formed in such a way that its periphery covers an are which forms the greater part of a full circle, merely a small fraction to 40) being occupied by the barrel. The inner band l2, however, on account of its position close to the bead, covers merely an arc which is somewhat larger than a semi-circle.

The common axis of the bands I I and [2 coincides with the line of sight so that merely the thin edges are seen and the thickness of the bands is so chosen that they present sharply defined thin lines to the eye during sighting operation.

As a rule the bands will be made of corrosion resistive steel but it is to be understood that any metal or alloy capable of answering the requirement as to rigidity, resistivity, etc, may be used.

The two circular bands ll, l2 may be used for range finding purposes, as will clearly be seen from Figures 4 and 5.

Let it be assumed that the distance between the eye E and the sighting device In is d and that the distance between the eye and the target T is D, and that the target just extends across the diameter of the inner circle, for example, the angle 2 a under which it is seen is identical with the angle under which the inner circle is seen.

The distance D of the target T is then defined exactly: This distance is equal to Eli 2 r or to T cota 1 being the radius of the inner circle and T the size of the target. This size in all practical cases is known as the size definitive of a specific species of game bird or of game is substantially constant.

For practical purposes the diameter T of the inner circle may be so chosen that the bird, game or other target appears to fill the inner circle when the target is, say, at the farthest range at which the gun or rifle will carry with full efiectiveness, or else at which this type of sight may be used with maximum efiiciency.

The diameter of the outer circle-may be so selected that the distance between it and the inner circle is equal to the diameter of the inner circle in which case the distance may be gauged immediately when the gun or rifle is pointed at the target. The outer circle have a multiple function. One of its functions consists in assisting in bringing the target into the right position within the sight. It will be clear that in the case of birds or of game the time for pointing the gun is extremely short. The effective range of a shot gun, for instance, is only about to yards, and most game birds will cover such a distance in not more than two seconds. However, it is comparatively easy to point the gun in such a way that the target appears within the outer 4 circle and it is then seen immediately whether the bird is still within range. Moreover it is easy to make the correction, bringing the target to the center, once it has been caught within the outer circle.

A second object of the outer circle consists in leading birds, game and other targets which are moving in a direction approximately perpendicular to the line of sight, into the center of the sight while evaluating the distance, so that, if necessary, some correction may be applied. It also serves for evaluating the speed with which the bird or game crosses the sight.

A third object consists in making the outer circle co-incident with a line of action, for instance, with the straying zone of a shot gun within which hits are still to be expected, when the target is within maximum efiiciency range. In this case the outer circle has to have a diameter in which it presents itself under a definite angle.

According to the example illustrated in Figures 4 and 5 the sight is mounted on a shot gun, on which the distance d between the eye and the bead is 36 inches.

The angle a under which the inner circle is seen is 0 24' and the angle under which the outer circle is seen is 0 12'. The diameter of the outer circle is then 3 times that of the inner circle. When the bird or game fills the inner circle or the distance between the inner and outer circles during the sighting operation it will be 30 yards from the point at which the rays of vision converge. The outer circle is larger enough to permit easy catching of a rapidly moving target within the outer circle of the sight and once this operation has been performed, the proper sighting is achieved within the shortest time, the person handling the gun being at the same time aware of the distance at which the target is found for the time being.

With these dimensions the outer circle also marks the contour of the stray zone of the shot gun under conditions at which hits may still be expected, provided the distance is less than the effective distance at which the target covers a diameter equal to that of the inner circle.

A further modification of the invention is shown in Figure 6 in which a sight is shown which has been milled out of the material out of which the barrel was made, so that it forms one piece with the latter.

Figures 7 and 8 finally show a modification of a sight which is to be mounted on a double barrelled gun. The construction is essentially that already described. However, the clamping band 24 has to encircle both barrels 25, 26 and in the middle a portion 21 is provided on which the inner circle 32 has to be mounted as the bead 28 in this case is arranged between the two barrels 25, 26.

The inner circle band 32 is thus reduced approximately to a semi-circle.

The outer circle band 3| may be welded or riveted to other portions of the clamping band 24 but in view of the transverse extension of the band 24 it is also reduced approximately to a semicircle.

The clamping band is clamped around the two barrels by means of a clamping screw 36 and a milled nut 31 in the manner already described.

Two barrelled guns in which the barrels are arranged one below the other may be provided with the sight much in the same way. The sight is, however, in this case mounted on the clamping band in the manner shown in. Figure 1, while the clamping band is extended to embrace both barrels. Its fixation may again be obtained by means of a clamping screw as shown.

It will be manifest that the gun sight as described has a number of advantages over known sights, among them is the improved way with which it is possible to get hold of the moving target by means of the outer circle. Once the target is within the outer circle a very exact evaluation of the distance can be made. Moreover, it becomes immediately apparent whether the target is within the shooting range. The centering of the target in the inner circle and also the evaluation of the speed of the target in a transverse direction are greatl facilitated. Moreover, the sight is simple in its construction and is easily removable and attachable. The latter feature permits to carry different specialized sights for diiferent bird or game species,

whereby the use of tables or of other reducing or translating means, or translation rules may be avoided or reduced to a minimum.

It will be clear to the expert that the material out of which the sight is made, the means for obtaining fixation of the sight on the rifle or gun, the nature of the gun and many other features may vary and may be changed Without in any way affecting the character of the invention.

I claim:

An interchangeable sighting and range finding device for a firearm comprising a barrel and a fixed front bead sight thereon, said sighting and range finding device comprising cla mping band adapted to encircle said barrel adjacent said bead sight, and "having a notch in an edge thereof within which said head sight seats to locate said clamping band in predetermined position with respect to said barrel, releasable means for tightening said clamping band upon said barrel, and a pair of arcuate sighting bands secured to said clamping band, said sighting bands being disposed concentrically one inside the other, the di- Number ameter of the innermost of said arcuate sighting bands being equal to the apparent size of a known target in the plane of said sighting and range finding device when said target is substantially at the maximum range of efiicient action of said firearm, and the diameter of the outermost of said arcuate bandsbeingsubstantially three times that o f s aid.innermost band whereby the distance between said bands is substantially equal to the diameter of said innermost band and the space between said arcuate bands on either the right hand side or the left hand side of said innermost band or the space within said innermost band can optionally be used as basis for comparison with the apparent size of a target, the common axis of said two arcuate sighting bands coinciding with sight line of said firearm which passes through the center of said fixed bead sight thereof.

LARRY M. SEYMORE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date Taylor June 2, 1896 Vickery Nov. 17, 1903 Bassell et al Nov. 28, 1905 Wise Mar. 5, 1907 Bassell et al Nov. 12, 1907 Knisley Feb. 5, 1935 Gaty Aug. 4, 1936 King Oct. 6, 1938 Bailey et a1 Oct. 9, 1945 Jefferies Jan. 6, 1948 FOREIGN PATENTS Country Date Great Britain 1933 France 1925 Number 

